Diesel engine



June 20,' 1933-` G. DoTTERwlcl-l 1,915,218.; l

DIESEL ENGINE Filed Sept. 14, 1929 'UNITED sf'rn'rrss .PATENT o-Frlca ozone or mmm; armut, Assreuon 'rc komm-winx! ,v :ummm mmueasnnnscmr'r von. nmz am'. vsrlvrxonlnnn. nommnAU, or ummm, enum, A conm or annimmt nmsnr. :mom

Application iled september 14, 1989. Serial lo. 388,614, and in Germany October 4,1988.

and have an often undesired high delay in In Diesel enginesv having the fuel injected without air and a supplementary combustion space with a restricted connection with the cylinder space, hitherto the fuel has either beenl injected into this supplementary space in what may be called the chamber type of engine, or it has been sprayed in through this space in what may be termed the prechmber type of engine. In `these kinds of engines,

the formation of the mixture for producing a combustion and an over-pressure in the supplementary combustion space takes place diferently. In the prechamber type of engine the fuel is sprayed from the cover of the chamber through the whole length of the' symmetrically ormed prechamber with the aid of injection pressure; in the other ty e of engine the fuel is atomized through t e cylinder space similarly by the spraying pressure in the chamber. 'In a particular class of engine, the filling process or the formation of eddies associated with it are merely used for the formation of the mixture in the chamber. In a further class of engine,

the formation of the mixture and the forma v tion of eddies were to be especially initiated between the divided spaces either .by 'sub- Y dividingthe chamber or by the differences in V pressure which'arise on ignition.

With progressive perfecting of the prechamber type of engine, the zone of strongest formation of mixture was situated more and more towards the restricted part. Constructions with flat pressed chambers arose, `and with multiple-jet fuel nozzles, for as the nozzle was movednearer to the restriction the formation of mixture in the chamber was insufficient. v v

All these kinds of construction of the prechamber type of engine,owing to the subl division o the combustion space, the violent eddying andthepartial combustion of the contents of the chamber, have a considerable ignition. Y l These disadvantages are avoided by the invention. The object ofthe invention consists of a Diesel engine with injection of the' fuel without air through a nozzle channel or passage leading into the cylinder. The essential feature of the invention consists fin an air store or reserve communicating on one side with the nozzle channel andpast which the fuel is injected.

Owing to the injection of the fuel past the air storage space, as later to be described, a formation of mixture takesplace during the injection stage in the-nozzle channel only, while in the air storage space itself .pure or almost pure air remains. The function of this air store is to supply fresh oggen present in the air constantly to the el in the nozzle'channel during the time of injection for maintaining the over-pressure, and after com letion of the injection stage, to ush the resu ting rich mixture as quickly an as completely as ssible out of the nozzle channel into the cy inder so that the next ensuing 1njection again takes place in pure air. Any

residues of the combustion in the nozzle channel are in this way oxidized. More moderate transfer of heat on the walls of the air space, lower consumption of fuel and eective carrying out of the ignition, `combustion and working ste s are the consequences.

A form ci) construction of the invention is illustrated by Way of example inthe annexed drawing. In this drawi the working cylinder is shown "at a, the piston at b, the cylinder head at c, the injecting valve at d, the 4 air store space at e, the combustion space at f and the nozzle channel at g. The latter, in the -form of construction in the drawing, is subdivided into an upper part adjoining the injection vnozzle rand a lower narrower part receiving a liningfan ignition lineror the like. 'e

45 transferencev of.Y heat tol thechamber walls The arrangement-is applicable in the case i of two cycle as well as four cycle engines. In

view of the correspondinglyv great erom-sectional area of the air stora space e as compared to the nozzle channe g there is only a ve minute pressure difference between these two. At the time of the beginning of the injection, which occurs just beforefthe inner dead end and just before the end of the compression stroke when the compressedair has reached or exceeded the ignition temperaturel of the fuel, the pressure difference between that in the cylinder roper and that in the air storage space e and) nozzle channely g is only suiciently large to cause a very` slight movement of air from the cylinder s pace f through the nozzle channel g lnto the air storage space e, and the ignition follows almost instantly without appreciable delay. No fuel or practically no fuel is therefore dis lled and carried back into the chamber e. I during the injection, a few individual particles of atomized fuel are carried into the air storage space e and there ignited, they will bel opposed by the air under pressure -wthinthe storage space until the pressure falls within the cylinder whereupon they will be expelled. No supplemental ignition is rused to empty the air storage space. The matter therein is expelled as a result of pressure differences and a regular operation and occurrence of ignition and combustion in proper sequence is assured. r

The air storage space eis valveless and air is supplied to the same during the compression stroke of the piston through nozzle channel g. The air compressed in the space e at the end of the com ression stroke is utilized in the combustion` uring the working stroke and the combustion products are removed during thel succeeding stroke. Clean air is drawn into the cylinder durin the following intake stroke and it is from t is air that the storage space e is supplied during the suc# ceeding compression stroke.

The'essence of the invention is not limited to any particular form and size of the air space. The drawing shows, by way of example, a bulb-shaped formation, and an arrangement in the cylinder head. The air space may also have any other suitable form and be separately inserted in the cylinder nating laterally in the nozzle channel, and a fuel valve in said cylinder head closing the nozzle channel to the outside and ada ted to inject liquid fuel through the nozzle c annel ast the mouth of the air storage chamber into the cylinder, the cross-sectionalarea of such air storage'space and of said channel being such that the difference in pressure between them and the space within the cylinder is negligible during compression.

In witness whereof I hereunto subscribe my name this 30th day of August 1929.

GEORG DOTTERWEIGH.

head or in the, workin cylinder, or ma also beinterchangeable. urther, different orms of construction of the nozzle channel are possibile.

In an internal combustion engine having compression i ition, the combination of a c linder, a piston mounted to reciprocatet erein, a c llnder head closing said cylinder at the com ustion end thereof and formed with a nozzle channel leading to said cylinder and serving as a mixin chamber, a valveless air storage chamber wit in said cylinder head one side of said nozzle channel and termi- 

